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Dubbo??????????????????????????Dubbo????????????????????????????????????MonitorFilter???????????????????????????????????????????????????????????????????

MonitorFilter?????

MonitorFilter?Dubbo???????????????????????????????????????????????????????????????????????????

MonitorFilter???

MonitorFilter???SPI??????Singleton?ThreadSafe??????????????????????????????????????@Activate?????Constants.PROVIDER?Constants.CONSUMER????????

/** * MonitorFilter. (SPI, Singleton, ThreadSafe) */@Activate(group = {Constants.PROVIDER, Constants.CONSUMER})public class MonitorFilter implements Filter {     // ??????}

getConcurrent????

getConcurrent???????????????????????ConcurrentMap?????????????????????????????

private AtomicInteger getConcurrent(Invoker invoker, Invocation invocation) {
    String key = invoker.getInterface().getName() + "." + invocation.getMethodName();
    AtomicInteger concurrent = concurrents.get(key);
    if (concurrent == null) {
        concurrents.putIfAbsent(key, new AtomicInteger());
        concurrent = concurrents.get(key);
    }
    return concurrent;
}

invoker????

invoker???MonitorFilter??????????????????????????????????????????????????????collect?????????

public Result invoke(Invoker invoker, Invocation invocation) throws RpcException {
    if (invoker.getUrl().hasParameter(Constants.MONITOR_KEY)) {
        RpcContext context = RpcContext.getContext();
        String remoteHost = context.getRemoteHost();
        long start = System.currentTimeMillis();
        getConcurrent(invoker, invocation).incrementAndGet();
        try {
            Result result = invoker.invoke(invocation);
            collect(invoker, invocation, result, remoteHost, start, false);
            return result;
        } catch (RpcException e) {
            collect(invoker, invocation, null, remoteHost, start, true);
            throw e;
        } finally {
            getConcurrent(invoker, invocation).decrementAndGet();
        }
    } else {
        return invoker.invoke(invocation);
    }
}

DubboMonitor????

Dubbo????????DubboMonitor???????????????????????DubboMonitor????????????????????????

DubboMonitor????

• ScheduledExecutorService??????????????????3????
• MonitorService??????????????Dubbo???????
• statisticsMap??????????ConcurrentMap???????

DubboMonitor????

DubboMonitor????????????????????????

public DubboMonitor(Invoker monitorInvoker, MonitorService monitorService) {
    this.monitorInvoker = monitorInvoker;
    this.monitorService = monitorService;
    this.monitorInterval = monitorInvoker.getUrl().getPositiveParameter("interval", 60000);
    sendFuture = scheduledExecutorService.scheduleWithFixedDelay(new Runnable() {
        @Override
        public void run() {
            try {
                send();
            } catch (Throwable t) {
                logger.error("Unexpected error occur at send statistic, cause: " + t.getMessage(), t);
            }
        }
    }, monitorInterval, monitorInterval, TimeUnit.MILLISECONDS);
}

send??

send???????????????MonitorService????????

public void send() {
    try {
        for (URL url = queue.take(); !queue.isEmpty(); url = queue.take()) {
            if (POISON_PROTOCOL.equals(url.getProtocol())) {
                continue;
            }
            // ?????????
            // ...
        }
    } catch (Throwable t) {
        logger.error("Unexpected error occur at send statistic, cause: " + t.getMessage(), t);
    }
}

Dubbo??????

Dubbo??????SimpleMonitorService????????????????????????????????????

SimpleMonitorService????

• ScheduledExecutorService??????????
• writeThread?????????????
• queue??????????????

write??

write???????????????????????????????? + ??? + ???

private void write() throws Exception {
    URL statistics = queue.take();
    if (POISON_PROTOCOL.equals(statistics.getProtocol())) {
        return;
    }
    // ???????????
    // ...
}

????

???Dubbo?????????????????????????????????????????????

???????Dubbo????????????????????????????????????????????????????????

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